﻿using System;
using System.IO;
using System.IO.Compression;

class ByteBuffer2D
{
    private static readonly int BOOL_SIZE = 1;
    //private static readonly int BYTE_SIZE = 1;
    //private static readonly int UINT16_SIZE = 2;
    private static readonly int INT_SIZE = 4;
    private static readonly int LONG_SIZE = 8;

    byte[] _tempBuff;
    byte[] _buff;
    private int _end = 0;
    public int Capacity { get; } = 0;

    public void Reset()
    {
        _end = 0;
    }

    public byte[] RawData()
    {
        return _buff;
    }

    public ByteBuffer2D(int size)
    {
        _buff = new byte[size];
        _tempBuff = new byte[LONG_SIZE];
        Capacity = size;
    }
    
    public void Push(SocketWeaver.FixedMath.FFloat value)
    {
        Push(value.Raw);
    }

    public void Push(SocketWeaver.FixedMath.FQuaternion value)
    {
        Push(value.RawX);
        Push(value.RawY);
        Push(value.RawZ);
        Push(value.RawW);
    }

    public void Push(SocketWeaver.FixedMath.FVector2 value)
    {
        Push(value.RawX);
        Push(value.RawY);
    }

    public void Push(SocketWeaver.FixedMath.FVector3 value)
    {
        Push(value.RawX);
        Push(value.RawY);
        Push(value.RawZ);
    }

    /*    
        public UInt32 id;
        public int count;

        public UInt32 k1;
        public FFloat n1;
        public FFloat t1;

        public UInt32 k2;
        public FFloat n2;
        public FFloat t2;

        public FVector2 relativeVelocity;
        public bool isTrigger;
     */

    //public void Push(PInternalState2D value)
    //{
    //    int count = value.contactCount;
    //    for(int i = 0; i < count; i++)
    //    {
    //        PContactExport2D export = value.contactExports[i];
    //        Push(export.count);
    //        Push(export.id);

    //        if (export.count > 0)
    //        {
    //            Push(export.k1);
    //            Push(export.n1);
    //            Push(export.t1);
    //        }

    //        if(export.count > 1)
    //        {
    //            Push(export.k2);
    //            Push(export.n2);
    //            Push(export.t2);
    //        }
    //    }
    //}

    void Push(bool value)
    {
        byte v = (byte)(value ? 1 : 0);
        _tempBuff[0] = v;

        Buffer.BlockCopy(_tempBuff, 0, _buff, _end, BOOL_SIZE);
        _end += BOOL_SIZE;
    }

    public void Push(int value)
    {
        _tempBuff[0] = (byte)(value >> 24);
        _tempBuff[1] = (byte)(value >> 16);
        _tempBuff[2] = (byte)(value >> 8);
        _tempBuff[3] = (byte)(value);

        Buffer.BlockCopy(_tempBuff, 0, _buff, _end, INT_SIZE);
        _end += INT_SIZE;
    }

    void Push(uint value)
    {
        _tempBuff[0] = (byte)(value >> 24);
        _tempBuff[1] = (byte)(value >> 16);
        _tempBuff[2] = (byte)(value >> 8);
        _tempBuff[3] = (byte)(value);

        Buffer.BlockCopy(_tempBuff, 0, _buff, _end, INT_SIZE);
        _end += INT_SIZE;
    }

    void Push(long value)
    {
        _tempBuff[0] = (byte)(value >> 56);
        _tempBuff[1] = (byte)(value >> 48);
        _tempBuff[2] = (byte)(value >> 40);
        _tempBuff[3] = (byte)(value >> 32);
        _tempBuff[4] = (byte)(value >> 24);
        _tempBuff[5] = (byte)(value >> 16);
        _tempBuff[6] = (byte)(value >> 8);
        _tempBuff[7] = (byte)(value);

        Buffer.BlockCopy(_tempBuff, 0, _buff, _end, LONG_SIZE);
        _end += LONG_SIZE;
    }

    void Push(ulong value)
    {
        _tempBuff[0] = (byte)(value >> 56);
        _tempBuff[1] = (byte)(value >> 48);
        _tempBuff[2] = (byte)(value >> 40);
        _tempBuff[3] = (byte)(value >> 32);
        _tempBuff[4] = (byte)(value >> 24);
        _tempBuff[5] = (byte)(value >> 16);
        _tempBuff[6] = (byte)(value >> 8);
        _tempBuff[7] = (byte)(value);

        Buffer.BlockCopy(_tempBuff, 0, _buff, _end, LONG_SIZE);
        _end += LONG_SIZE;
    }

    static readonly uint[] table = {
            0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
            0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
            0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
            0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
            0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
            0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
            0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
            0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
            0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
            0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
            0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
            0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
            0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
            0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
            0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
            0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
            0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
            0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
            0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
            0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
            0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
            0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
            0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
            0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
            0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
            0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
            0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
            0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
            0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
            0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
            0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
            0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
            0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
            0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
            0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
            0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
            0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
            0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
            0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
            0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
            0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
            0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
            0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
        };

    public uint Hash()
    {
        uint result = 0;
        int start = 0;
        int end = _end;

        result = result ^ ~0U;

        for (int i = 0; i < start + _end; i++)
        {
            result = table[(result ^ _buff[i]) & 0xFF] ^ (result >> 8);
        }

        return result ^ ~0U; 
    }

    public double Compress()
    {
        double originalSize = _end;
        _buff = ByteArrayCompressionUtility.Compress(_buff, _end);

        double compressedSize = _buff.Length;
        _end = _buff.Length;

        return compressedSize / originalSize;
    }

    public void Decompress()
    {
        _buff = ByteArrayCompressionUtility.Decompress(_buff, _end);
    }

    public uint Length()
    {
        return (uint)_end;
    }

    //http://toreaurstad.blogspot.com/2014/01/compressing-byte-array-in-c-with.html
    public static class ByteArrayCompressionUtility
    {
        private static int BUFFER_SIZE = 64 * 1024; //64kB

        public static byte[] Compress(byte[] inputData, int length)
        {
            if (inputData == null)
                throw new ArgumentNullException("inputData must be non-null");

            using (var compressIntoMs = new MemoryStream())
            {
                using (var gzs = new BufferedStream(new GZipStream(compressIntoMs,
                 CompressionMode.Compress), BUFFER_SIZE))
                {
                    gzs.Write(inputData, 0, length);
                }
                return compressIntoMs.ToArray();
            }
        }

        public static byte[] Decompress(byte[] inputData, int length)
        {
            if (inputData == null)
                throw new ArgumentNullException("inputData must be non-null");

            using (var compressedMs = new MemoryStream(inputData, 0, length))
            {
                using (var decompressedMs = new MemoryStream())
                {
                    using (var gzs = new BufferedStream(new GZipStream(compressedMs,
                     CompressionMode.Decompress), BUFFER_SIZE))
                    {
                        gzs.CopyTo(decompressedMs);
                    }
                    return decompressedMs.ToArray();
                }
            }
        }
    }
}

